Coal mining roof concentrated water gushing early warning method
By constructing a multi-factor comprehensive early warning model and combining indicators such as micro-seismicity, water level changes, and support resistance, the problem of insufficient early warning of concentrated water gushing from the roof during coal mining has been solved, achieving more accurate early warning and improved safety.
Patent Information
- Application Number
- CN202510812618.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-18
- Publication Date
- 2025-09-26
AI Technical Summary
Existing technologies cannot effectively warn of concentrated water inrush from the roof during coal mining, resulting in insufficient safety, and the advanced water drainage method lacks specificity and accuracy.
A multi-factor comprehensive early warning model is constructed, combining microseismic warning, water level change rate, support resistance, mining speed, low-resistance abnormal area, water filling scale index and TDS. Through comprehensive judgment of multiple early warning indicators, accurate early warning of concentrated water gushing from the roof can be achieved.
It provides a more accurate early warning of concentrated water inrush from the roof, which can avoid mine disasters in a timely manner and improve mining safety and production guidance.
Smart Images
Figure CN120701410A_ABST
Abstract
Description
Technical Field The present invention belongs to the technical field of mine water prevention and control, and in particular relates to an early warning method for concentrated water inrush from a coal mine roof. Background Art Water exploration and drainage operations in coal mine working faces are crucial elements of coal mining. During the mining process, delamination spaces form within the working face. Once these spaces are filled with water, concentrated water inrush occurs. To accelerate clean and efficient development and utilization, improve energy supply quality, utilization efficiency, and carbon reduction, targeted prevention and control measures are needed to prevent concentrated water inrush from the roof. At present, most coal mines use advance drainage before working face mining to prevent and control mine water; however, as mining geological conditions change, advance drainage alone cannot prevent the occurrence of concentrated water gushing from the mine mining roof. The early warning of concentrated water inrush from the roof needs to fully consider the evolution law of the mining-induced overburden structure, dynamically analyze the geological and hydrogeological conditions of the roof, and then select appropriate monitoring indicators for comprehensive early warning. However, relying solely on advance drainage before mining is not targeted and accurate, and cannot effectively guarantee mining safety. In view of this, the present invention is proposed. Summary of the Invention In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is: A method for early warning of concentrated water inrush from a coal mine roof comprises the following steps: S1. Based on the order in which different rock layers break and generate cracks during mining, select microseismic early warning indicators, build a microseismic early warning model, and obtain microseismic early warning signals; S2. Based on the roof water level change rate, a water level change rate warning discrimination model is constructed, and a water level change rate warning signal is calculated based on the water level change rate warning discrimination model; S3. constructing a support resistance warning model based on the support resistance warning index of concentrated water inrush, and calculating a support resistance warning signal based on the support resistance warning model; S4. Based on the different volumes of water accumulated in the absorptive space at different mining speeds, a mining speed warning model is constructed and a mining speed warning signal is calculated; S5. Based on the low-resistance abnormal area caused by water-rich fracture zones, broken rock masses, water-conducting structures, lithology differences, etc., a low-resistance abnormal area early warning model is constructed to obtain a low-resistance abnormal area early warning signal; S6. Construct a water filling scale indicator warning model based on unit water inflow and crack-production ratio, and calculate the water filling scale indicator warning signal S7. Based on the different TDS of groundwater in different aquifers, a TDS indicator early warning model is constructed to obtain TDS indicator early warning signals based on the TDS changes after water accumulation in the goaf caused by mining; S8. Based on microseismic warning, water level warning, support resistance warning, mining speed warning, low resistance abnormal area warning, water filling scale index warning and TDS warning, a multi-factor comprehensive warning model is constructed to obtain the multi-factor comprehensive warning indicator results. As a priority of the present invention, in step S1, a microseismic early warning model is constructed for different fracture sequences of the upper rock layer and the lower aquiclude during mining: (1) The fracture model of only the upper rock layer is as follows: RMR1=sta(AE)·sta(E)·sta(T1) In the above formula, sta() represents the standardization of the indicators. In order to unify the microseismic early warning of the entire mine (mining area), according to the change scale of each microseismic early warning indicator of the mined working face, the daily total energy AE, the average energy per time E, greater than 10 3 The standardized scales (minimum and maximum values) of the total number of microseismic days T1 are (0, 1000), (0, 10), and (0, 30), respectively. (2) The model for the rupture of only the lower aquiclude is as follows: According to the change scale of each microseismic early warning index of the mined working face, the total number of daily AN and less than 10 3 The standardized scales (minimum and maximum values) of the total number of microseismic days T2 are (0, 100) and (0, 30), respectively. (3) The coordinated fracture model of the upper rock layer and the lower aquiclude is as follows: RMR3=sta(AN)·sta(AE) As a priority of the present invention, a microseismic comprehensive early warning model is constructed based on the above three microseismic early warning models to calculate and obtain a microseismic early warning signal M; The microseismic comprehensive early warning model is: M= <RMR t -RMR0> In the above formula, < > is the discriminant function, and RMR t represents the comprehensive early warning index of microseismic events at time t, RMR0 is the early warning threshold of microseismic events, M is 1 when it indicates that the index has reached the early warning threshold, and 0 when it indicates that the index has not reached the early warning threshold. As a priority of the present invention, in step S2, the water level change rate of the aquifer during concentrated water inflow is selected as the early warning indicator; The water level change rate calculation formula is: v c =h d -h d-1 In the above formula, h d-1 and hd They are the aquifer water level at 12:00 the previous day and the water level at 12:00 the current day. c >0 means the water level is rising, otherwise it is falling. As a priority of the present invention, based on the water level change speed warning discrimination model, a water level change warning signal V is calculated; The water level change speed early warning discrimination model is: V= <v c0 -v cd > In the above formula, <> is the discriminant function, v cd Indicates the speed of water level change; v c0 The water level change rate warning threshold is -1 m / d. A value of 1 indicates that the indicator has reached the warning threshold; a value of 0 indicates that the indicator has not reached the warning threshold. As a priority of the present invention, in step S4, the support resistance warning index MP of concentrated water inrush is calculated according to the following formula: In the above formula, τ is the average volume force of the rock mass, F is the resistance at the end of the support cycle; S is the top beam area, H c It is the distance between the roof of the lower aquiclude and the roof of the coal seam. As a priority of the present invention, the support resistance early warning model is: S= <SR t -SR0> In the above formula, <> is the discriminant function, SR t represents the stent resistance warning indicator at time t; SR0 is the stent resistance warning threshold; S is 1 if the indicator has reached the warning threshold; 0 if the indicator has not reached the warning threshold. The threshold for the stent resistance warning signal is 0.95. As a priority of the present invention, in step S4, the mining speed will affect the amount of water accumulated in the stratum. Taking the mining advance distance L as an example (the working face width is a), considering safety factors, assuming that the coverage area of the stratum is equal to the area of the mining advance distance L, its dynamic recharge can be calculated as follows based on the principle of groundwater dynamics: The daily dynamic supply when the abscission layer forms the maximum space: Q d =q1·a+q2·a+q3·L+q4·L The number of days required to advance the total distance L is: d max =L / v Therefore, when the total distance L is advanced, the total volume of water in the detached space is: In the above formula The maximum value of n is As a priority of the present invention, the mining speed warning model is: C= <v t -v0> In the above formula, <> is the discriminant function, v t represents the working face advance speed at time t; v0 is the advance speed warning threshold; C is 1 if the indicator reaches the warning threshold; 0 if the indicator does not reach the warning threshold. The advance speed warning signal threshold is 3 m / d. As a priority of the present invention, in step S5, the low-resistance abnormal area early warning model is: D= <d t -d0> In the above formula, <> is the discriminant function, d t represents the apparent resistivity of the working face at time t; d0 is the apparent resistivity warning threshold; D is 1 if the indicator reaches the warning threshold; 0 if the indicator does not reach the warning threshold. The threshold for the apparent resistivity warning signal is 25Ω. As a priority of the present invention, in step S6, the water filling scale index I of the abscission space is calculated according to the following formula: In the above formula, q represents the water-richness of the aquifer at this moment, R represents the degree of development of water-conducting fractures, q0 is the warning threshold of unit water yield, and R0 is the warning threshold of the fracture-production ratio. As a priority of the present invention, the water filling scale indicator early warning model is: T= (9-27) In the above formula, <> is the discriminant function, T is 1, indicating that the indicator has reached the warning threshold; 0, indicating that the indicator has not reached the warning threshold. As a priority of the present invention, in step S7, the TDS indicator warning model is: TDS= <TDS t -TDS0> In the above formula, <> is the discriminant function, TDS t represents the TDS content of the water sample at time t, and TDS0 represents the initial TDS content of the water sample. A TDS value of 1 indicates that the indicator has reached the warning threshold; a value of 0 indicates that the indicator has not reached the warning threshold. The TDS warning threshold is 8500 mg / L.
[0001] As a priority of the present invention, in step S8, the comprehensive early warning model is:
[0002] f=T·(V·TDS+C)·(M·S+D)
[0003] In the above formula: T, V, TDS, C, M, S, and D represent the water filling scale warning signal, water level change speed warning signal, TDS warning signal, propulsion speed warning signal, microseismic warning signal, support resistance warning signal, and low resistance abnormal area warning signal, respectively. 1 indicates that the indicator reaches the warning threshold, and 0 indicates that the indicator does not reach the warning threshold; q0 and R0 represent the unit water inflow warning threshold and its warning threshold, respectively; v cd and v c0 Respectively represent the water level change speed and its warning threshold on that day; TDS t and TDS0 represent the TDS content and its warning threshold at time t respectively; v t and v0 represent the production speed and its warning threshold at time t respectively; RMR t and RMR0 represent the microseismic comprehensive early warning index and its early warning threshold at time t, respectively; SR t and SR0 represent the comprehensive warning index of support resistance and its warning threshold at time t respectively; d t and d0 represent the apparent resistivity of the working face at time t and its warning threshold, respectively. When the comprehensive warning index f≥1, the centralized water inrush warning is activated. Compared with the prior art, the present invention has the following beneficial effects: The present invention fully considers the evolution mechanism of water accumulation, and on this basis comprehensively considers factors such as advancement speed, water filling scale, water level, microseismicity, support resistance, low-resistance abnormal area, TDS, etc. under different engineering geological conditions, and establishes a multi-factor comprehensive early warning index. It can accurately warn of concentrated water gushing from the roof of the mining working face, and can provide more guiding reference for timely disaster avoidance during actual mine production. The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS In the attached figure: Figure 1 This is a schematic diagram of the coal mine roof concentrated water inrush early warning principle based on multiple factor indicators provided by the present invention. DETAILED DESCRIPTION In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention. Example: like Figure 1 As shown, a method for early warning of concentrated water inrush from the roof of a coal mine comprises the following steps: S1. Based on the order in which different rock layers break and generate cracks during mining, select microseismic early warning indicators, build a microseismic early warning model, and obtain microseismic early warning signals; S2. Based on the roof water level change rate, a water level change rate warning discrimination model is constructed, and a water level change rate warning signal is calculated based on the water level change rate warning discrimination model; S3. constructing a support resistance warning model based on the support resistance warning index of concentrated water inrush, and calculating a support resistance warning signal based on the support resistance warning model; S4. Based on the different volumes of water accumulated in the absorptive space at different mining speeds, a mining speed warning model is constructed and a mining speed warning signal is calculated; S5. Based on the low-resistance abnormal area caused by water-rich fracture zones, broken rock masses, water-conducting structures, lithology differences, etc., a low-resistance abnormal area early warning model is constructed to obtain a low-resistance abnormal area early warning signal; S6. Construct a water filling scale indicator warning model based on unit water inflow and crack-production ratio, and calculate the water filling scale indicator warning signal S7. Based on the different TDS of groundwater in different aquifers, a TDS indicator early warning model is constructed to obtain TDS indicator early warning signals based on the TDS changes after water accumulation in the goaf caused by mining; S8. Based on microseismic warning, water level warning, support resistance warning, mining speed warning, low resistance abnormal area warning, water filling scale index warning and TDS warning, a multi-factor comprehensive warning model is constructed to obtain the multi-factor comprehensive warning indicator results. As a priority of the present invention, in step S1, a microseismic early warning model is constructed for different fracture sequences of the upper rock layer and the lower aquiclude during mining: (1) The fracture model of only the upper rock layer is as follows: RMR1=sta(AE)·sta(E)·sta(T1) In the above formula, sta() represents the standardization of the indicators. In order to unify the microseismic early warning of the entire mine (mining area), according to the change scale of each microseismic early warning indicator of the mined working face, the daily total energy AE, the average energy per time E, greater than 10 3 The standardized scales (minimum and maximum values) of the total number of microseismic days T1 are (0, 1000), (0, 10), and (0, 30), respectively. (2) The model for the rupture of only the lower aquiclude is as follows: According to the change scale of each microseismic early warning index of the mined working face, the total number of daily AN and less than 10 3 The standardized scales (minimum and maximum values) of the total number of microseismic days T2 are (0, 100) and (0, 30), respectively. (3) The coordinated fracture model of the upper rock layer and the lower aquiclude is as follows: RMR3=sta(AN)·sta(AE) As a priority of the present invention, a microseismic comprehensive early warning model is constructed based on the above three microseismic early warning models to calculate and obtain a microseismic early warning signal M; The microseismic comprehensive early warning model is: M= <RMR t -RMR0> In the above formula, <> is the discriminant function, RMR t represents the comprehensive early warning index of microseismic events at time t, RMR0 is the early warning threshold of microseismic events, M is 1 when it indicates that the index has reached the early warning threshold, and 0 when it indicates that the index has not reached the early warning threshold. As a priority of the present invention, in step S2, the water level change rate of the aquifer during concentrated water inflow is selected as the early warning indicator; The water level change rate calculation formula is: v c =h d -h d-1 In the above formula, h d-1 and h d They are the aquifer water level at 12:00 the previous day and the water level at 12:00 the current day. c >0 means the water level is rising, otherwise it is falling. As a priority of the present invention, based on the water level change speed warning discrimination model, a water level change warning signal V is calculated; The water level change speed early warning discrimination model is: V= <v c0 -v cd > In the above formula, <> is the discriminant function, v cd Indicates the speed of water level change; v c0 The water level change rate warning threshold is -1 m / d. A value of 1 indicates that the indicator has reached the warning threshold; a value of 0 indicates that the indicator has not reached the warning threshold. As a priority of the present invention, in step S4, the support resistance warning index MP of concentrated water inrush is calculated according to the following formula: In the above formula, τ is the average volume force of the rock mass, F is the resistance at the end of the support cycle; S is the top beam area, H c It is the distance between the roof of the lower aquiclude and the roof of the coal seam. As a priority of the present invention, the support resistance early warning model is: S= <SR t -SR0> In the above formula, <> is the discriminant function, SR t represents the stent resistance warning indicator at time t; SR0 is the stent resistance warning threshold; S is 1 if the indicator has reached the warning threshold; 0 if the indicator has not reached the warning threshold. The threshold for the stent resistance warning signal is 0.95. As a priority of the present invention, in step S4, the mining speed will affect the amount of water accumulated in the stratum. Taking the mining advance distance L as an example (the working face width is a), considering safety factors, assuming that the coverage area of the stratum is equal to the area of the mining advance distance L, its dynamic recharge can be calculated as follows based on the principle of groundwater dynamics: The daily dynamic supply when the abscission layer forms the maximum space: Q d =q1·a+q2·a+q3·L+q4·L The number of days required to advance the total distance L is: d max =L / v Therefore, when the total distance L is advanced, the total volume of water in the detached space is: In the above formula The maximum value of n is As a priority of the present invention, the mining speed warning model is: C= <v t -v0> In the above formula, <> is the discriminant function, v t represents the working face advance speed at time t; v0 is the advance speed warning threshold; C is 1 if the indicator reaches the warning threshold; 0 if the indicator does not reach the warning threshold. The advance speed warning signal threshold is 3 m / d. As a priority of the present invention, in step S5, the low-resistance abnormal area early warning model is: D= <d t -d0> In the above formula, <> is the discriminant function, d t represents the apparent resistivity of the working face at time t; d0 is the apparent resistivity warning threshold; D is 1 if the indicator reaches the warning threshold; 0 if the indicator does not reach the warning threshold. The threshold for the apparent resistivity warning signal is 25Ω. As a priority of the present invention, in step S6, the water filling scale index I of the abscission space is calculated according to the following formula: In the above formula, q represents the water-richness of the aquifer at this moment, R represents the degree of development of water-conducting fractures, q0 is the warning threshold of unit water yield, and R0 is the warning threshold of the fracture-production ratio. As a priority of the present invention, the water filling scale indicator early warning model is: T= (9-27) In the above formula, < > is the discriminant function, and T is 1, indicating that the indicator has reached the warning threshold; 0, indicating that the indicator has not reached the warning threshold. As a priority of the present invention, in step S7, the TDS indicator warning model is: TDS= <TDS t -TDS0> In the above formula, <> is the discriminant function, TDS t represents the TDS content of the water sample at time t, and TDS0 represents the initial TDS content of the water sample. A TDS value of 1 indicates that the indicator has reached the warning threshold; a value of 0 indicates that the indicator has not reached the warning threshold. The TDS warning threshold is 8500 mg / L.
[0004] As a priority of the present invention, in step S8, the comprehensive early warning model is:
[0005] f=T·(V·TDS+C)·(M·S+D)
[0006] In the above formula: T, V, TDS, C, M, S, and D represent the water filling scale warning signal, water level change speed warning signal, TDS warning signal, propulsion speed warning signal, microseismic warning signal, support resistance warning signal, and low resistance abnormal area warning signal, respectively. 1 indicates that the indicator reaches the warning threshold, and 0 indicates that the indicator does not reach the warning threshold; q0 and R0 represent the unit water inflow warning threshold and its warning threshold, respectively; v cd and v c0 Respectively represent the water level change speed and its warning threshold on that day; TDS t and TDS0 represent the TDS content and its warning threshold at time t respectively; v t and v0 represent the production speed and its warning threshold at time t respectively; RMR t and RMR0 represent the microseismic comprehensive early warning index and its early warning threshold at time t, respectively; SR t and SR0 represent the comprehensive warning index of support resistance and its warning threshold at time t respectively; d t and d0 represent the apparent resistivity of the working face at time t and its warning threshold, respectively. When the comprehensive warning index f≥1, the centralized water inrush warning is activated. Compared with the existing technology, the present invention provides a method for warning of concentrated water gushing from the roof of a coal mine, which fully considers the evolution mechanism of water accumulation. On this basis, it comprehensively considers factors such as advancement speed, water filling scale, water level, micro-seismicity, support resistance, low-resistance abnormal area, TDS, etc. under different engineering geological conditions, and establishes a multi-factor comprehensive warning index. It can accurately warn of concentrated water gushing from the roof of the mining working face, and can provide more guiding reference for timely disaster avoidance during actual mine production. According to S1-S7, a multi-factor comprehensive early warning model is constructed based on microseismic early warning, water level early warning, support resistance early warning, mining speed early warning, low resistance abnormal area early warning, water filling scale index early warning and TDS early warning index selection. T, V, TDS, C, M, S, and D represent the water filling scale warning signal, water level change speed warning signal, TDS warning signal, propulsion speed warning signal, microseismic warning signal, support resistance warning signal, and low resistance abnormal area warning signal, respectively. 1 indicates that the indicator reaches the warning threshold, and 0 indicates that the indicator does not reach the warning threshold; q0 and R0 represent the unit water inflow warning threshold and its warning threshold, respectively; v cd and v c0 Respectively represent the water level change speed and its warning threshold on that day; TDS t and TDS0 represent the TDS content and its warning threshold at time t respectively; v t and v0 represent the production speed and its warning threshold at time t respectively; RMR t and RMR0 represent the microseismic comprehensive early warning index and its early warning threshold at time t, respectively; SR t and SR0 represent the comprehensive warning index of support resistance and its warning threshold at time t respectively; d t and d0 represent the apparent resistivity of the working face at time t and its warning threshold, respectively. When the comprehensive warning index f ≥ 1, the disaster warning is activated. The method for early warning of concentrated water inrush from the roof of a coal mine based on multi-factor indicators provided in this embodiment fully considers the changes in geological factors during the mining process, analyzes the mechanical mechanism of the formation of water guide channels during the mining of the working face, and on this basis comprehensively considers microseismicity, water level change rate, support resistance, mining speed, low-resistance abnormal area, water filling scale index and TDS to establish a multi-factor comprehensive early warning index. This method can accurately warn of concentrated water inrush from the roof of the mining working face and provide more guiding suggestions for water hazard prevention and control during mine production. The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of this application. It should be understood that the above description is only the specific implementation methods of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application should be included in the scope of protection of this application.
Claims
1. A method for early warning of concentrated water inrush from the roof of a coal mine, characterized in that: The steps include: Step S1: based on the order in which different rock layers break and generate cracks during mining, select microseismic early warning indicators, build a microseismic early warning model, and obtain a microseismic early warning signal; Step S2: Based on the roof water level change rate, a water level change rate warning discrimination model is constructed, and a water level change rate warning signal is obtained by calculation according to the water level change rate warning discrimination model; Step S3: constructing a support resistance warning model based on the support resistance warning index of concentrated water inrush, and calculating a support resistance warning signal based on the support resistance warning model; Step S4: Based on the different volumes of water accumulated in the absorptive space at different pushing and mining speeds, a pushing and mining speed warning model is constructed and a pushing and mining speed warning signal is calculated; Step S5: constructing a low-resistance abnormal area warning model based on the low-resistance abnormal area caused by water-rich fracture zones, broken rock masses, water-conducting structures, lithology differences, etc., and obtaining a low-resistance abnormal area warning signal; Step S6: construct a water filling scale indicator warning model based on the unit water inflow and the crack production ratio, and calculate the water filling scale indicator warning signal Step S7: Based on the different TDS of groundwater in different aquifers, a TDS indicator early warning model is constructed based on the TDS change after water accumulation in the goaf caused by mining, and a TDS indicator early warning signal is obtained; Step S8: Based on microseismic warning, water level warning, support resistance warning, mining speed warning, low resistance abnormal area warning, water filling scale index warning and TDS warning, a multi-factor comprehensive warning model is constructed to obtain a multi-factor comprehensive warning indicator result.
2. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 1, characterized in that: In step S1, a microseismic early warning model is constructed for the fracture sequence of the upper and lower rock layers: (1) The fracture model of only the upper rock layer is as follows: RMR1=sta(AE)·sta(E)·sta(T1) Among them, sta() represents the standardization of the indicators. In order to unify the microseismic early warning of the entire mine, the daily total energy AE, the average energy E per time, and the value greater than 10 are selected according to the change scale of each microseismic early warning indicator of the mined working face. 3 The standardized scale of the total number of microseismic days T1 is as follows: the minimum and maximum values are (0, 1000), (0, 10), and (0, 30), respectively. (2) The model for the rupture of only the lower aquiclude is as follows: According to the change scale of each microseismic early warning index of the mined working face, the total number of daily AN and less than 10 3 The standardized scale of the total number of microseismic days T2: the minimum and maximum values are (0, 100) and (0, 30), respectively. (3) The coordinated fracture model of the upper rock layer and the lower aquiclude is as follows: RMR3 = sta(AN)·sta(AE).
3. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 2, characterized in that: Based on the above three microseismic early warning models, a comprehensive microseismic early warning model is constructed to calculate the microseismic early warning signal M; The microseismic comprehensive early warning model is: M=<RMR t -RMR0> Among them, < > is the discriminant function, RMR t represents the comprehensive early warning index of microseismic events at time t, RMR0 is the early warning threshold of microseismic events, M is 1 when it indicates that the index has reached the early warning threshold, and 0 when it indicates that the index has not reached the early warning threshold.
4. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 1, characterized in that: In step S2, for the change in the water level of the aquifer during concentrated water inflow, the water level change rate is selected as the early warning indicator; The water level change rate calculation formula is: v c =h d -h d-1 Among them, h d-1 and h d are the aquifer water level at 12:00 the previous day and the water level at 12:00 the current day; v c >0 means the water level is rising, otherwise it is falling.
5. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 4, characterized in that: Based on the water level change speed warning discrimination model, the water level change warning signal V is calculated; The water level change speed early warning discrimination model is: V= <v c0 -v cd > Among them, < > is the discriminant function, v cd Indicates the speed of water level change; v c0 is the water level change rate warning threshold; V is 1, indicating that the indicator has reached the warning threshold; 0 indicates that the indicator has not reached the warning threshold; the water level change rate warning threshold is -1m / d.
6. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 1, characterized in that: In step S3, the support resistance warning index SR of concentrated water inrush is calculated according to the following formula: Where τ is the average volume force of the rock mass, F is the resistance at the end of the support cycle; S is the area of the top beam, H c It is the distance between the roof of the lower aquiclude and the roof of the coal seam.
7. A coal mine roof concentrated water inrush early warning method according to claim 6, characterized in that: The support resistance early warning model is: S=<SR t -SR0> Among them, < > is the discriminant function, SR t represents the stent resistance warning indicator at time t; SR0 is the stent resistance warning threshold; S is 1 when it means the indicator reaches the warning threshold; 0 when it means the indicator does not reach the warning threshold; the threshold of the stent resistance warning signal is 0.
95.
8. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 1, characterized in that: In step S4, the mining speed will affect the amount of water accumulated in the stratum. Taking the mining advance distance L as an example (the working face width is a), considering safety factors, assuming that the coverage area of the stratum is equal to the area of the mining advance distance L, its dynamic recharge can be calculated as follows based on the principle of groundwater dynamics: The daily dynamic supply when the abscission layer forms the maximum space: <h2 style=";text-align:left;direction:ltr">Q<h2 style=";text-align:left;direction:ltr"> d <h2 style=";text-align:left;direction:ltr"> =q1·a+q2·a+q3·L+q4·L The number of days required to advance the total distance L is: d max =L / v Therefore, when the total distance L is advanced, the total volume of water accumulated in the detachment layer is: in The maximum value of n is 9. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 8, characterized in that ,The ,pre-warning model for ,propulsion speed is: C=<v t -v0> Among them, < > is the discriminant function, v t represents the working face advance speed at time t; v0 is the advance speed warning threshold; C is 1, indicating that the indicator has reached the warning threshold; 0 indicates that the indicator has not reached the warning threshold; the advance speed warning signal threshold is 3m / d; In step S5, the low-resistance abnormal area early warning model is: D= <d t -d0> Among them, < > is the discriminant function, d t represents the apparent resistivity of the working face at time t; d0 is the apparent resistivity warning threshold; D is 1 if the indicator reaches the warning threshold; 0 if the indicator does not reach the warning threshold; the threshold of the apparent resistivity warning signal is 25Ω; In step S6, the abscission layer water filling scale index I is calculated according to the following formula: Among them, q represents the water-richness of the aquifer at this moment, R represents the degree of development of water-conducting fractures, q0 is the warning threshold for unit water yield, and R0 is the warning threshold for the fracture-production ratio.
10. The method for early warning of concentrated water inrush from the roof of a coal mine according to claim 1, characterized in that: The water filling scale indicator early warning model is: T＝ Among them, < > is the discriminant function, T is 1 if the indicator reaches the warning threshold; 0 if the indicator does not reach the warning threshold; In step S7, the TDS indicator early warning model is: TDS=<TDS t -TDS0> Among them, < > is the discriminant function, TDS t represents the TDS content of the water sample at time t, TDS0 represents the initial TDS content of the water sample; TDS value 1 indicates that the indicator has reached the warning threshold; 0 indicates that the indicator has not reached the warning threshold; the TDS warning threshold is 8500 mg / L; In step S8, the comprehensive early warning model is: f=T·(V·TDS+C)·(M·S+D) Where: T, V, TDS, C, M, S, and D represent the water filling scale warning signal, water level change speed warning signal, TDS warning signal, propulsion speed warning signal, microseismic warning signal, support resistance warning signal, and low resistance abnormal area warning signal, respectively. 1 indicates that the indicator reaches the warning threshold, and 0 indicates that the indicator does not reach the warning threshold; q0 and R0 represent the unit water inflow warning threshold and its warning threshold, respectively; v cd and v c0 Respectively represent the water level change speed and its warning threshold on that day; TDS t and TDS0 represent the TDS content and its warning threshold at time t respectively; v t and v0 represent the production speed and its warning threshold at time t respectively; RMR t and RMR0 represent the microseismic comprehensive early warning index and its early warning threshold at time t, respectively; SR t and SR0 represent the comprehensive warning index of support resistance and its warning threshold at time t respectively; d t and d0 represent the apparent resistivity of the working face at time t and its warning threshold respectively; when the comprehensive warning index f≥1, the disaster warning is activated.